This invention relates to an electromagnetic-shielding gasket installed in a gap of a joint of a conductive housing (hereinafter referred to as a housing) for containing electronic components or in a gap of a joint between a housing and a closure.
Recently, office equipments such as electronic typewriters and printers, household appliances such as washing machines and vacuum cleaners and the like increasingly use electronic components such as microcomputers. Even automobiles equipped with electronic control systems for fuel injection and the like are becoming very common. Thus, the number of microcomputers is increasing, and the clock frequency of microcomputers is also becoming higher. Consequently, the noise generated from electronic components leaks and enters through the gap in the housing of electronic components, and can be transmitted to other electronic components. The noise may cause malfunctions to the overall equipment as well as the electronic components.
To shield electronic components from electromagnetic waves, an electromagnetic-shielding gasket is usually inserted into a gap in the housing of the electronic components. The electromagnetic-shielding gasket comprises a resilient core covered with a metal mesh. By installing the gasket in the gap of the joint in the housing, electromagnetic waves are reflected and/or absorbed by the conductive housing and the gasket. The electronic components in the housing are thus protected from electromagnetic waves.
Conventionally, the electromagnetic-shielding gasket comprises the resilient core so as to fit in the gap of the joint of the housing easily. The gasket has also enough durability against the compression of the core. However, the metal mesh is not resilient and thus deforms greatly at the corner of the core which deforms elastically to a great extent, when the core is compressed frequently by the closure and the like. As a result, the metal mesh may break, and the gasket therefore can not shield the electronic components sufficiently from electromagnetic waves.